可以帮忙解释一下下面这些代码分别表示什么函数和什么意思嘛?
%% 采集数据并绘图
% data = zeros(1, 1000);
data = [];
num = 1;
led_state = 1;
%% 采集数据并绘图,根据采集值改变PWM占空比
pic = plot(nan);
xlim([0 1000]);
ylim([0 3.3]);
xlabel('Points');
ylabel('Voltage');
grid on;
while 1
if(num <= 1000)
data(num) = readRegister(PCF8591, hex2dec('40'));
% writePWMDutyCycle(mypi, 16, data(num) / 255);
num = num + 1;
set(pic, 'YData', data*3.3/255, 'Marker', 'o');
drawnow;
else
num = 1;
data = [];
writeLED(mypi, 'led0', led_state);
set(pic, 'YData', data*3.3/255, 'Marker', 'o');
drawnow;
end
led_state = ~led_state;
end